Could alterations in maternal plasma visfatin concentration participate in the phenotype definition of preeclampsia and SGA?

Objective.?Women with preeclampsia and those who delivered a small-for-gestational-age (SGA) neonate share several mechanisms of disease, including chronic uteroplacental ischemia and failure of physiologic transformation of the spiral arteries. However, the clinical manifestation of these obstetrical syndromes is remarkably different. It has been proposed that an altered maternal metabolic state, as well as a unique circulating cytokines milieu, predispose women to develop either preeclampsia or SGA. Compelling evidence suggests that adipose tissue orchestrates both metabolic pathways and immunological responses via the production of adipokines. Visfatin is a novel adipocytokine with metabolic and immunomodulating properties. The objective of this study was to determine whether preeclampsia and SGA are associated with alterations in maternal circulating visfatin concentrations.

Methods.?This cross-sectional study included pregnant women in the following groups: (1) normal pregnancy (n?=?158); (2) patients with preeclampsia (n?=?43) of which 32 had an AGA and 11 had an SGA neonate; (3) patients without preeclampsia who delivered an SGA neonate (n?=?55). Maternal plasma visfatin concentrations were measured by ELISA. Nonparametric tests and multiple linear regression analysis were used.

Results.?(1) Women who delivered an SGA neonate had a higher median maternal plasma visfatin concentration than those with a normal pregnancy (20.0?ng/ml, interquartile range: 17.2–24.6 vs. 15.2?ng/ml, 12.1–19.2, respectively; P?<?0.001) and than those with preeclampsia (14.5?ng/ml, 12.5–18.7; P?<?0.001); (2) the median maternal plasma visfatin concentration did not differ significantly between patients with preeclampsia and those with a normal pregnancy (P?=?0.8); (3) among patients with preeclampsia, there was no significant difference in the median maternal plasma visfatin concentration between those with or without an SGA neonate (P?=?0.5); (4) in a linear regression model, delivery of an SGA neonate and pregestational body mass index were independently associated with increased visfatin concentration after adjustment for confounding factors (maternal age, smoking, gestational age at blood collection and the presence of preeclampsia or SGA).

Conclusion.?(1) Patients with SGA, but not those with preeclampsia, had a higher maternal plasma visfatin concentration than those with a normal pregnancy; (2) this finding suggests differential involvement of visfatin in SGA and preeclampsia; (3) we propose that changes in circulating maternal visfatin concentration may be implicated in the phenotypic definitions and distinction of preeclampsia and SGA.     

Normal pregnancy is characterized by systemic activation of the complement system

Background.?The complement system, a major component of innate immunity, has recently been implicated in the mechanisms of fetal loss and placental inflammation in the anti-phospholipid antibody syndrome. Inhibition of complement has been proposed as an absolute requirement for normal pregnancy. Yet, pregnancy is characterized by a generalized activation of the innate immune system. This study was conducted to determine whether or not normal pregnancy is associated with complement activation in the maternal circulation.

Methods.?Anaphylatoxins (C3a, C4a and C5a) were determined in the plasma of normal pregnant (20–42 wks; n?=?134) and non-pregnant women (n?=?40). These complement split products (C3a, C4a and C5a) were measured using specific immunoassays. Non-parametric statistics were used for analysis.

Results.?1) The median plasma concentrations of C3a, C4a and C5a were significantly higher in normal pregnant women than in non-pregnant women (all p?<?0.001); 2) the concentration of C3a, C4a and C5a did not change with gestational age (p?>?0.05); and 3) the median plasma concentration of C3a had a positive correlation with the plasma C4a and C5a concentrations (r?=?0.36, p?<?0.001 and r?=?0.35, p?<?0.001, respectively).

Conclusion.?1) Normal human pregnancy is associated with evidence of complement activation, as determined by higher concentrations of the anaphylatoxins C3a, C4a and C5a in the maternal circulation; and 2) we propose that physiologic activation of the complement system during pregnancy is a compensatory mechanism aimed at protecting the host against infection.     

The profiles of soluble adhesion molecules in the “great obstetrical syndromes”*

Objective: The objective of this study was to determine the profiles of maternal plasma soluble adhesion molecules in patients with preeclampsia, small-for-gestational-age (SGA) fetuses, acute pyelonephritis, preterm labor with intact membranes (PTL), preterm prelabor rupture of the membranes (preterm PROM), and fetal death.

Materials and methods: A cross-sectional study was conducted to determine maternal plasma concentrations of sE-selectin, sL-selectin, and sP-selectin as well as sICAM-1, sVCAM-1, and sPECAM-1 in patients with (1) an uncomplicated pregnancy (control, n?=?100); (2) preeclampsia (n?=?94); (3) SGA fetuses (in women without preeclampsia/hypertension, n?=?45); (4) acute pyelonephritis (n?=?25); (5) PTL (n?=?53); (6) preterm PROM (n?=?24); and (7) fetal death (n?=?34). Concentrations of soluble adhesion molecules and inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-8) were determined with sensitive and specific enzyme-linked immunoassays.

Results: In comparison to women with a normal pregnancy, (1) women with preeclampsia had higher median concentrations of sE-selectin, sP-selectin, and sVCAM-1, and a lower concentration of sL-selectin (all p values?p values?p values?p values?p values?p values p values?Conclusions: The results of this study show that endothelial cell activation/dysfunction reflected by the plasma concentration of sE-selectin is not specific to preeclampsia but is present in pregnancies complicated by SGA fetuses, acute pyelonephritis, and fetal death. Collectively, we report that each obstetrical syndrome appears to have a stereotypical profile of soluble adhesion molecules in the peripheral circulation.     

Endocan,a putative endothelial cell marker,is elevated in preeclampsia,decreased in acute pyelonephritis,and unchanged in other obstetrical syndromes

Objective: Endocan, a dermatan sulphate proteoglycan produced by endothelial cells, is considered a biomarker for endothelial cell activation/dysfunction. Preeclampsia is characterized by systemic vascular inflammation, and endothelial cell activation/dysfunction. Therefore, the objectives of this study were to determine whether: (1) plasma endocan concentrations in preeclampsia differ from those in uncomplicated pregnancies; (2) changes in plasma endocan concentration relate to the severity of preeclampsia, and whether these changes are specific or observed in other obstetrical syndromes such as small-for-gestational age (SGA), fetal death (FD), preterm labor (PTL) or preterm prelabor rupture of membranes (PROM); (3) a correlation exists between plasma concentration of endocan and angiogenic (placental growth factor or PlGF)/anti-angiogenic factors (soluble vascular endothelial growth factor receptor or sVEGFR-1, and soluble endoglin or sEng) among pregnancies complicated by preeclampsia; and (4) plasma endocan concentrations in patients with preeclampsia and acute pyelonephritis (both conditions in which there is endothelial cell activation) differ.

Method: This cross-sectional study included the following groups: (1) uncomplicated pregnancy (n?=?130); (2) preeclampsia (n?=?102); (3) pregnant women without preeclampsia who delivered an SGA neonate (n?=?51); (4) FD (n?=?49); (5) acute pyelonephritis (AP; n?=?35); (6) spontaneous PTL (n?=?75); and (7) preterm PROM (n?=?64). Plasma endocan concentrations were determined in all groups, and PIGF, sEng and VEGFR-1 plasma concentrations were measured by ELISA in the preeclampsia group.

Results: (1) Women with preeclampsia had a significantly higher median plasma endocan concentration than those with uncomplicated pregnancies (p?=?0.004); (2) among women with preeclampsia, the median plasma endocan concentration did not differ significantly according to disease severity (p?=?0.1), abnormal uterine artery Doppler velocimetry (p?=?0.7) or whether diagnosis was made before or after 34 weeks gestational age (p?=?0.3); (3) plasma endocan concentration in women with preeclampsia correlated positively with plasma anti-angiogenic factor concentrations [sVEGFR-1: Spearman rho 0.34, p?=?0.001 and sEng: Spearman rho 0.30, p?=?0.003]; (4) pregnancies complicated by acute pyelonephritis with bacteremia had a lower median plasma endocan concentration than pregnancies complicated by acute pyelonephritis without bacteremia (p?=?0.004), as well as uncomplicated pregnancies (p?=?0.001); and (5) there was no significant difference in the median plasma endocan concentration between uncomplicated pregnancies and those complicated by FD, delivery of an SGA neonate, PTL or preterm PROM (other members of the “great obstetrical syndromes”; each p?>?0.05).

Conclusion: Median maternal plasma endocan concentrations were higher preeclampsia and lower in acute pyelonephritis with bacteremia than in uncomplicated pregnancy. No significant difference was observed in the median plasma endocan concentration between other great obstetrical syndromes and uncomplicated pregnancies. The difference in the direction of change of endocan in preeclampsia and acute pyelonephritis with bacteremia may be consistent with the view that both disease entities differ in pathogenic mechanisms, despite their associations with systemic vascular inflammation and endothelial cell activation/dysfunction.     

Tissue factor activity in women with preeclampsia or SGA: a potential explanation for the excessive thrombin generation in these syndromes

Objective: The aim of this study was to determine whether the activity of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in the plasma of women with preeclampsia (PE) and small for gestational age (SGA) neonate differ from that of normal pregnant women and whether they are related to specific placental lesions.

Methods: This cross-sectional study included the following groups: (1) normal pregnancy (n?=?68); (2) PE (n=?128); and (3) SGA (n?=?56). Maternal plasma TF and TFPI activity was determined with chromogenic assays.

Results: (1) The median maternal plasma TF activity, but not TFPI activity, differed among the study groups (p?p?=?.4, respectively); (2) patients with PE had a higher median maternal plasma TF activity than women with normal pregnancies (p?p?=?.002); (3) among patients with PE, those with distal villous hypoplasia had a higher median maternal TF activity than those without these placental lesions (p?=?.018); and (4) following adjustment for confounding variables, maternal plasma TF and TFPI activity were not associated with an SGA neonate.

Conclusions: Plasma TF activity is higher in women with PE than in those with SGA or normal pregnancies. We propose that these changes may be responsible, at least in part, for the increased in-vivo thrombin generation observed in this obstetrical syndrome.     

Low maternal concentrations of soluble vascular endothelial growth factor receptor-2 in preeclampsia and small for gestational age

Objectives. Preeclampsia is considered an anti-angiogenic state. A role for the anti-angiogenic factors soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and soluble endoglin in preeclampsia has been proposed. Soluble vascular endothelial growth factor receptor-2 (sVEGFR-2) has been detected in human plasma, and the recombinant form of this protein has anti-angiogenic activity. There is a paucity of information about maternal plasma sVEGFR-2 concentrations in patients with preeclampsia and those without preeclampsia with small for gestational age (SGA) fetuses. This study was conducted to determine whether: (1) plasma sVEGFR-2 concentration changes throughout pregnancy; and (2) preeclampsia and SGA are associated with abnormalities in the maternal plasma concentration of sVEGFR-2.

Study design. This cross-sectional study included non-pregnant women (n = 40), women with normal pregnancies (n = 135), women with an SGA fetus (n = 53), and women with preeclampsia (n = 112). SGA was defined as an ultrasound-estimated fetal weight below the 10^th percentile for gestational age that was confirmed by neonatal birth weight. Plasma concentrations of sVEGFR-2 were determined by ELISA.

Results. (1) There was no significant difference in the mean plasma concentration of sVEGFR-2 between non-pregnant women and those with normal pregnancies (p = 0.8); (2) patients with preeclampsia and those without preeclampsia with SGA fetuses had a lower mean plasma concentration of sVEGFR-2 than that of women with normal pregnancies (p < 0.001 for both); and (3) there was no significant difference in the mean plasma concentration of sVEGFR-2 between patients with preeclampsia and those without preeclampsia with SGA (p = 0.9).

Conclusions. Preeclampsia and SGA are associated with low plasma concentrations of sVEGFR-2. One interpretation of the findings is that plasma sVEGFR-2 concentration could reflect endothelial cell function.     

The maternal plasma soluble vascular endothelial growth factor receptor-1 concentration is elevated in SGA and the magnitude of the increase relates to Doppler abnormalities in the maternal and fetal circulation

Objectives. The soluble form of vascular endothelial growth factor receptor-1 (sVEGFR-1), an antagonist to vascular endothelial growth factor and placental growth factor, has been implicated in the pathophysiology of preeclampsia. Preeclampsia and pregnancy complicated with small for gestational age (SGA) fetuses share some pathophysiologic derangements, such as failure of physiologic transformation of the spiral arteries, endothelial cell dysfunction, and leukocyte activation. The objectives of this study were to: (1) determine whether plasma concentrations of sVEGFR-1 in mothers with SGA fetuses without preeclampsia at the time of diagnosis are different from those in patients with preeclampsia or normal pregnant women, and (2) examine the relationship between plasma concentrations of sVEGFR-1 and Doppler velocimetry in uterine and umbilical arteries in patients with preeclampsia and those with SGA.

Study design. A cross-sectional study was conducted to determine the concentrations of the soluble form of VEGFR-1 in plasma obtained from normal pregnant women (n = 135), women with SGA fetuses (n = 53), and patients with preeclampsia (n = 112). Patients with SGA fetuses and those with preeclampsia were sub-classified according to the results of uterine and umbilical artery Doppler velocimetry examinations. Plasma concentrations of sVEGFR-1 were determined by an ELISA. Since these concentrations change with gestational age, differences among various subgroups were statistically estimated with the delta value, defined as the difference between the observed and expected plasma sVEGFR-1 concentration. The expected values were derived from regression analysis of plasma sVEGFR-1 concentrations in normal pregnancy. Regression analysis and univariate and multivariate analysis were employed.

Results. (1) Mothers with SGA fetuses had a mean plasma concentration of sVEGFR-1 higher than normal pregnant women (p < 0.001), but lower than patients with preeclampsia (p < 0.001). (2) Among patients with SGA fetuses, only those with abnormal uterine artery Doppler velocimetry had a mean plasma sVEGFR-1 concentration significantly higher than normal pregnant women (p < 0.001). (3) Among mothers with SGA fetuses in whom Doppler velocimetry was performed (n = 41), those with abnormalities in both the uterine and umbilical artery velocimetry had the highest mean delta of sVEGFR-1 plasma concentration (mean ± standard deviation (SD): 0.69 ± 0.29). Conversely, patients who had normal Doppler velocimetry in both uterine and umbilical arteries had the lowest mean delta (mean ± SD: 0.09 ± 0.29) of sVEGFR-1 plasma concentrations (ANOVA; p < 0.001). (4) Among patients with preeclampsia in whom Doppler velocimetry was performed (n = 69), those with abnormalities in both the uterine and umbilical artery velocimetry had the highest mean delta sVEGFR-1 plasma concentration (mean ± SD: 1.01 ± 0.22) among all groups classified (ANOVA; p < 0.001). (5) Among patients with SGA and those with preeclampsia, there was a relationship (Chi-square for trend p < 0.001 for both) between the severity of Doppler velocimetry abnormalities and the proportion of patients who had high delta sVEGFR-1 plasma concentrations (defined as a concentration two standard deviations (2SD) above the mean delta of normal pregnant women). (6) Multiple regression analysis suggested that the diagnostic category (e.g., SGA or preeclampsia), Doppler abnormalities, and gestational age at blood sampling were associated with an increase in plasma sVEGFR-1 concentrations (p < 0.001).

Conclusions. These observations provide support for the participation of the soluble receptor of vascular endothelial growth factor in the pathophysiology of SGA with abnormal uterine artery Doppler velocimetry and preeclampsia. An excess of sVEGFR-1 is released into the maternal circulation of patients with preeclampsia and those with SGA fetuses, as abnormalities of impedance to blood flow involve uterine and umbilical circulation.     

Evidence for complement activation in the amniotic fluid of women with spontaneous preterm labor and intra-amniotic infection

Objective.?The complement system plays an important role in host defense against infection. Concentrations of complement split products or anaphylatoxins (C3a, C4a, and C5a) in biological fluids are considered to reflect complement activation. The purpose of this study was to determine if term and preterm parturition are associated with evidence of complement activation in the amniotic fluid.

Study design.?Amniotic fluid (AF) samples were collected from 270 women in the following groups: (1) normal pregnant women in midtrimester (n = 70), (2) term not in labor (n = 23), (3) term in labor (n = 48), and (4) preterm labor (PTL) (n = 129). PTL was categorized into: (a) PTL without microbial invasion of the amniotic cavity (MIAC) who delivered at term (n = 42), (b) PTL who delivered preterm without MIAC (n = 57), and (c) PTL with MIAC (n = 30). C5a, C4a, and C3a concentrations in amniotic fluid were determined by ELISA. Nonparametric tests were used for statistical analysis.

Results.?(1) The median AF C5a concentration was higher in women at term than that of those in the midtrimester (p = 0.02); (2) Spontaneous labor at term was not associated with changes in AF concentrations of anaphylatoxins C3a, C4a, and C5a (all p > 0.05); (3) Among patients with PTL who delivered preterm, those with MIAC had higher AF C4a and C5a concentrations than those without infection (p < 0.01); and (4) AF C3a, C4a, and C5a concentrations were higher in patients with PTL with MIAC than in those with PTL without MIAC who delivered at term.

Conclusion.?Patients with spontaneous preterm labor and intact membranes with microbial invasion of the amniotic cavity had higher median amniotic fluid concentration of complement split products C3a, C4a, and C5a than patients without intra-amniotic infection. These findings suggest that preterm labor in the context of infection is associated with activation of the complement system.     

Unexplained fetal death: Another anti-angiogenic state

Background.?Pregnancy creates a unique situation in which both vasculogenesis and extensive angiogenesis are required for successful fetal and placental development. Recently, the soluble form of vascular endothelial growth factor (VEGF) receptor-1 (sVEGFR-1), an antagonist to VEGF and placental growth factor (PlGF) (two important angiogenic factors), has been implicated in the pathophysiology of preeclampsia and small for gestational age (SGA) without preeclampsia. There is, however, a paucity of information concerning plasma sVEGFR-1 concentrations in other obstetrical disorders. The purpose of this study was to determine plasma sVEGFR-1 concentrations in normal pregnancy, term gestation in labor, and in patients with pregnancy complications including spontaneous preterm labor, preterm premature rupture of the membranes (PROM), fetal death, and acute pyelonephritis.

Methods.?A cross-sectional study was conducted to determine the concentrations of sVEGFR-1 in plasma obtained from 499 women in the following groups: (1) non-pregnant women (n = 40); (2) pregnant women (n = 135); (3) normal pregnant women at term in labor (n = 60); (4) fetal death (n = 60); (5) spontaneous preterm labor with intact membranes (n = 102); (6) preterm PROM (n = 64); and (7) pregnancy with acute pyelonephritis (n = 38). Since plasma sVEGFR-1 concentration changes with gestational age, the difference between the actual and the expected plasma sVEGFR-1 concentration (derived from regression equation of normal pregnancy) for each patient (delta value) was calculated and used to examine the differences of plasma sVEGFR-1 concentrations among various groups. Plasma concentrations of sVEGFR-1 were determined by enzyme-linked immunoassay. Regression analysis and non-parametric statistics were used for analysis.

Results.?(1) Normal pregnant women before term had a median plasma sVEGFR-1 concentration significantly higher than non-pregnant women (p < 0.001); (2) plasma sVEGFR-1 concentration increased with advancing gestational age in normal pregnancy (r = 0.5; p < 0.001); (3) there was no significant difference in the median delta plasma concentration of sVEGFR-1 between normal pregnant women at term with and without labor (p = 0.09); (4) patients with fetal death had a median delta plasma concentration of sVEGFR-1 significantly higher than normal pregnant women (p = 0.001). Among patients with fetal death, those with unexplained causes (p = 0.04) and those with preeclampsia (p < 0.001) had a significantly higher delta plasma sVEGFR-1 concentration than normal pregnant women; and (5) there was no significant difference in the median delta plasma sVEGFR-1 concentration between normal pregnancy and preterm labor with intact membranes, preterm PROM (regardless of the presence or absence of microbial invasion of the amniotic cavity), or acute pyelonephritis (all p > 0.05).

Conclusions.?Plasma sVEGFR-1 concentration is increased in a subset of patients with fetal death, but does not change in term and preterm parturition, rupture of fetal membranes, or acute pyelonephritis.     

Preeclampsia is associated with an elevation of plasma sMet concentrations in the second trimester

Abstract

Objective: The aim of this study was to investigate the association between anti-angiogenic factor soluble c-Met (sMet) concentrations in maternal plasma and the risk of preeclampsia.

Methods: The pregnant women included in this study (1) had subsequent preeclampsia (n?=?52) and were compared to normal controls (n?=?104) at the time of amniocentesis (15–20 weeks); and (2) had preeclampsia (n?=?63) and were compared to normal controls (n?=?112) at the time of diagnosis of preeclampsia (29–40 weeks). sMet concentrations were measured by ELISA. Non-parametric statistics were used for analysis.

Results: Maternal plasma sMet concentrations were significantly higher in both women with subsequent preeclampsia (median: 1372.7?ng/ml versus 1100.5?ng/ml; p?=?0.036) and women with preeclampsia (median: 1651.9?ng/ml versus 1364.7?ng/ml; p?<?0.001) than in the controls. After adjusting for potential confounding factors, the risks of developing preeclampsia were as follows: adjusted odds ratio 2.5 (95% confidence interval, 1.2–5.2; p?=?0.016) for second trimester sMet concentration with a cut-off value of 1223.5?ng/ml and 4.4 (95% confidence interval, 2.2–9.1; p?<?0.001) for third trimester sMet concentration with a cut-off value of 1460.3?ng/ml.

Conclusion: Elevated maternal plasma sMet concentrations were independently associated with the increased risk of preeclampsia.     

Placental growth hormone is increased in the maternal and fetal serum of patients with preeclampsia

Objectives. Placental growth hormone (PGH) is a pregnancy-specific protein produced by syncytiotrophoblast and extravillous cytotrophoblast. No other cells have been reported to synthesize PGH Maternal. PGH Serum concentration increases with advancing gestational age, while quickly decreasing after delivery of the placenta. The biological properties of PGH include somatogenic, lactogenic, and lipolytic functions. The purpose of this study was to determine whether the maternal serum concentrations of PGH change in women with preeclampsia (PE), women with PE who deliver a small for gestational age neonate (PE + SGA), and those with SGA alone.

Study design. This cross-sectional study included maternal serum from normal pregnant women (n = 61), patients with severe PE (n = 48), PE + SGA (n = 30), and SGA alone (n = 41). Fetal cord blood from uncomplicated pregnancies (n = 16) and PE (n = 16) was also analyzed. PGH concentrations were measured by ELISA. Non-parametric statistics were used for analysis.

Results. (1) Women with severe PE had a median serum concentration of PGH higher than normal pregnant women (PE: median 23,076 pg/mL (3473–94 256) vs. normal pregnancy: median 12 157 pg/mL (2617–34 016); p < 0.05), pregnant women who delivered an SGA neonate (SGA: median 10 206 pg/mL (1816–34 705); p < 0.05), as well as pregnant patients with PE and SGA (PE + SGA: median 11 027 pg/mL (1232–61 702); p < 0.05). (2) No significant differences were observed in the median maternal serum concentration of PGH among pregnant women with PE and SGA, SGA alone, and normal pregnancy (p > 0.05). (3) Compared to those of the control group, the median umbilical serum concentration of PGH was significantly higher in newborns of preeclamptic women (PE: median 356.1 pg/mL (72.6–20 946), normal pregnancy: median 128.5 pg/mL (21.6–255.9); p < 0.01). (4) PGH was detected in all samples of cord blood.

Conclusions. (1) PE is associated with higher median concentrations of PGH in both the maternal and fetal circulation compared to normal pregnancy. (2) Patients with PE + SGA had lower maternal serum concentrations of PGH than preeclamptic patients without SGA. (3) Contrary to previous findings, PGH was detectable in the fetal circulation. The observations reported herein are novel and suggest that PGH may play a role in the mechanisms of disease in preeclampsia and fetal growth restriction.     

Pentraxin 3 in maternal circulation: An association with preterm labor and preterm PROM,but not with intra-amniotic infection/inflammation

Objective.?Pentraxin 3 (PTX3) is an acute-phase protein that has an important role in the regulation of the innate immune response. The aim of this study was to determine if maternal plasma PTX3 concentration changes in the presence of intra-amniotic infection and/or inflammation (IAI) in women with preterm labor (PTL) and intact membranes, as well as those with preterm prelabor rupture of membranes (preterm PROM).

Study design.?This cross-sectional study included women in the following groups: (1) nonpregnant (n?=?40); (2) uncomplicated pregnancies in the first (n?=?22), second (n?=?22) or third trimester (n?=?71, including 50 women at term not in labor); (3) uncomplicated pregnancies at term with spontaneous labor (n?=?49); (4) PTL and intact membranes who delivered at term (n?=?49); (5) PTL without IAI who delivered preterm (n?=?26); (6) PTL with IAI (n?=?65); (7) preterm PROM without IAI (n?=?25); and (8) preterm PROM with IAI (n?=?77). Maternal plasma PTX3 concentrations were determined by ELISA.

Results.?(1) Maternal plasma PTX3 concentrations increased with advancing gestational age (r?=?0.62, p?<?0.001); (2) women at term with spontaneous labor had a higher median plasma PTX3 concentration than those at term not in labor (8.29?ng/ml vs. 5.98?ng/ml, p?=?0.013); (3) patients with an episode of PTL, regardless of the presence or absence of IAI and whether these patients delivered preterm or at term had a higher median plasma PTX3 concentration than normal pregnant women (p?<?0.001 for all comparisons); (4) similarly, patients with preterm PROM, with or without IAI had a higher median plasma PTX3 concentration than normal pregnant women (p?<?0.001 for both comparisons); and (5) among patients with PTL and those with preterm PROM, IAI was not associated with significant changes in the median maternal plasma PTX3 concentrations.

Conclusions.?The maternal plasma PTX3 concentration increases with advancing gestational age and is significantly elevated during labor at term and in the presence of spontaneous preterm labor or preterm PROM. These findings could not be explained by the presence of IAI, suggesting that the increased PTX3 concentration is part of the physiologic or pathologic activation of the pro-inflammatory response in the maternal circulation during the process of labor at term or preterm.     

Fetal death: A condition with a dissociation in the concentrations of soluble vascular endothelial growth factor receptor-2 between the maternal and fetal compartments

Objective.?An anti-angiogenic state has been implicated in the pathophysiology of preeclampsia, fetal growth restriction and fetal death. Vascular endothelial growth factor (VEGF), an indispensible angiogenic factor for embryonic and placental development exerts its angiogenic properties through the VEGF receptor (VEGFR)-2. A soluble form of this protein (sVEGFR-2) has been recently detected in maternal blood. The aim of this study was to determine if fetal death was associated with changes in the concentrations of sVEGFR-2 in maternal plasma and amniotic fluid.

Study Design.?Maternal plasma was obtained from patients with fetal death (n?=?59) and normal pregnant women (n?=?134). Amniotic fluid was collected from 36 patients with fetal death and the control group consisting of patients who had an amniocentesis and delivered at term (n?=?160). Patients with fetal death were classified according to the clinical circumstances into the following groups: (1) unexplained; (2) preeclampsia and/or placental abruption; (3) chromosomal and/or congenital anomalies. Plasma and amniotic fluid concentrations of sVEGFR-2 were determined by ELISA. Non-parametric statistics and logistic regression analysis were applied.

Results.?(1) Patients with a fetal death had a significantly lower median plasma concentration of sVEGFR-2 than normal pregnant women (p?<?0.001). The median plasma concentration of sVEGFR-2 in patients with unexplained fetal death and in those with preeclampsia/abruption, but not that of those with congenital anomalies, was lower than that of normal pregnant women (p?=?0.006, p?<?0.001 and p?=?0.2, respectively); (2) the association between plasma sVEGFR-2 concentrations and preterm unexplained fetal death remained significant after adjusting for potential confounders (OR: 3.2; 95% CI: 1.4–7.3 per each quartile decrease in plasma sVEGFR-2 concentrations); (3) each subgroup of fetal death had a higher median amniotic fluid concentration of sVEGFR-2 than the control group (p?<?0.001 for each); (4) the association between amniotic fluid sVEGFR-2 concentrations and preterm unexplained fetal death remained significant after adjusting for potential confounders (OR: 15.6; 95% CI: 1.5–164.2 per each quartile increase in amniotic fluid sVEGFR-2 concentrations); (5) among women with fetal death, there was no relationship between maternal plasma and amniotic fluid concentrations of sVEGFR-2 (Spearman Rho: 0.02; p?=?0.9).

Conclusion.?Pregnancies with a fetal death, at the time of diagnosis, are characterized by a decrease in the maternal plasma concentration of sVEGFR-2, but an increase in the amniotic fluid concentration of this protein. Although a decrease in sVEGFR-2 concentration in maternal circulation depends upon the clinical circumstances of fetal death, an increase in sVEGFR-2 concentration in amniotic fluid seems to be a common feature of fetal death. It remains to be determined if the perturbation in sVEGFR-2 concentrations in maternal and fetal compartments observed herein preceded the death of a fetus.     

Leukocytes of pregnant women with small-for-gestational age neonates have a different phenotypic and metabolic activity from those of women with preeclampsia

Objective.?Preeclampsia and pregnancies complicated by small-for-gestational age (SGA) neonates share several underlying mechanisms of disease. However, while an exaggerated systemic maternal inflammatory response is regarded as one of the hallmarks of the pathogenesis of preeclampsia, the presence of a similar systemic intra-vascular inflammation in mothers of SGA neonates without hypertension is controversial. The aim of this study was to determine phenotypic and metabolic changes in granulocytes and monocytes of women who develop preeclampsia and those who deliver an SGA neonate, compared to normal pregnant women.

Methods.?This cross-sectional study included patients with a normal pregnancy (n?=?33), preeclampsia (n?=?33), and an SGA without preeclampsia (n?=?33), matched for gestational age at blood sample collection. Granulocyte and monocyte phenotypes were determined by flow cytometry, using monoclonal antibodies against selective cluster of differentiation (CD) antigens. The panel of antibodies included the following: CD11b, CD14, CD16, CD18, CD49d, CD62L, CD64, CD66b, and HLA-DR. Intracellular reactive oxygen species (iROS) were assessed at the basal state and after stimulation (oxidative burst). Results were reported as mean channel brightness (MCB) or intensity of detected fluorescence. Analysis was conducted with non-parametric statistics. A p-value?<?0.01 was considered statistically significant.

Results.?(1) Women who delivered an SGA neonate had a higher MCB of CD11b in granulocytes and monocytes than those with a normal pregnancy (p?<?0.001 for both); (2) patients with preeclampsia had a lower median MCB of CD62L in granulocytes (p?=?0.006) and a higher median basal iROS and oxidative burst in monocytes than women with an SGA neonate (p?=?0.003 and p?=?0.002, respectively).

Conclusion.?Pregnancies complicated by the delivery of an SGA neonate are characterized by a higher activation of maternal peripheral leukocytes than in normal pregnancies, but lower than in pregnancies complicated by preeclampsia.     

Maternal serum soluble CD30 is increased in normal pregnancy,but decreased in preeclampsia and small for gestational age pregnancies

Objective. Women with preeclampsia and those who deliver small for gestational age (SGA) neonates are characterized by intravascular inflammation (T helper 1 (Th1)-biased immune response). There is controversy about the T helper 2 (Th2) response in preeclampsia and SGA. CD30, a member of the tumor necrosis factor receptor superfamily, is preferentially expressed in vitro and in vivo by activated T cells producing Th2-type cytokines. Its soluble form (sCD30) has been proposed to be an index of Th2 immune response. The objective of this study was to determine whether the maternal serum concentration of sCD30 changes with normal pregnancy, as well as in mothers with preeclampsia and those who deliver SGA neonates.

Methods. This cross-sectional study included patients in the following groups: (1) non-pregnant women (N = 49); (2) patients with a normal pregnancy (N = 89); (3) patients with preeclampsia (N = 100); and (4) patients who delivered an SGA neonate (N = 78). Maternal serum concentration of sCD30 was measured by a specific and sensitive enzyme-linked immunoassay. Non-parametric tests with post-hoc analysis were used for comparisons. A p value <0.05 was considered statistically significant.

Results. (1) The median sCD30 serum concentration of pregnant women was significantly higher than that of non-pregnant women (median 29.7 U/mL, range 12.2–313.2 vs. median 23.2 U/mL, range 14.6–195.1, respectively; p = 0.01). (2) Patients with preeclampsia had a significantly lower median serum concentration of sCD30 than normal pregnant women (median 24.7 U/mL, range 7.6–71.2 vs. median 29.7 U/mL, range 12.2–313.2, respectively; p < 0.05). (3) Mothers with SGA neonates had a lower median concentration of sCD30 than normal pregnant women (median 23.4 U/mL, range 7.1–105.3 vs. median 29.7 U/mL, range 12.2–313.2, respectively; p < 0.05). (4) There was no significant correlation (r = ?0.059, p = 0.5) between maternal serum sCD30 concentration and gestational age (19–38 weeks) in normal pregnant women.

Conclusions. (1) Patients with preeclampsia and those who deliver an SGA neonate had a significantly lower serum concentration of sCD30 than normal pregnant women. (2) This finding is consistent with the view that preeclampsia and SGA are associated with a polarized Th1 immune response and, perhaps, a reduced Th2 response.     

Maternal anti-protein Z antibodies in pregnancies complicated by pre-eclampsia,SGA and fetal death

Objective.?Low maternal plasma protein Z (PZ) concentrations were reported in patients with pre-eclampsia (PE), a small for gestational age (SGA) neonate, and a fetal demise (FD). Anti-protein Z antibodies (APZ-AB) have been proposed as a possible underlying mechanism leading to low plasma PZ concentrations. The objective of this study was to determine the maternal plasma concentration of APZ-AB in women with a normal pregnancy, and patients with PE, an SGA neonate or a FD.

Study design.?A cross-sectional study included women in the following groups: (1) non-pregnant women (n = 45); and pregnant women with: (2) normal pregnancies (n = 70); (3) PE (n = 123); (4) SGA neonates (n = 51); and (5) a FD (n = 51). Plasma concentrations of anti-protein Z IgM and IgG antibodies were measured by ELISA. Elevated APZ-AB was defined as >75th, 90th and 95th percentile of the normal pregnancy group. Non-parametric statistics were used for analyses.

Results.?(1) Patients with an SGA neonate had a higher median maternal plasma IgG APZ-AB concentration than women with normal pregnancies (p < 0.001), and patients with PE (p < 0.001) or with a FD (p = 0.001). (2) The proportion of patients with a maternal plasma IgM APZ-AB concentration >90th percentile was higher in the SGA group than in the PE group (p = 0.01). (3) Patients with PE maternal plasma IgM APZ-AB concentration >90th percentile had a higher rate of villous thrombosis (p = 0.03) and persistent muscularisation of basal plate arteries (p = 0.01) than those with IgM APZ-AB concentration <90th percentile; and (5) Patients with FD and maternal plasma IgM APZ-AB concentration >90th percentile had a higher rate of umbilical phlebitis and arteritis than those with IgM APZ-AB concentration <90th percentile (p = 0.003).

Conclusions.?(1) Patients with SGA neonates have a higher median plasma concentration of IgG APZ-AB than normal pregnant women, or patients with PE or FD; and (2) maternal plasma IgM APZ-AB concentration >90th percentile was associated with vascular placental lesions in patients with PE, but not in those with an SGA neonate, suggesting that in a subset of patients, these antibodies can be associated with abnormal placentation and pregnancy complications.     

CXCL10/IP-10: A missing link between inflammation and anti-angiogenesis in preeclampsia?

Objective. Interferon (IFN)-γ inducible protein, CXCL10/IP-10, is a member of the CXC chemokine family with pro-inflammatory and anti-angiogenic properties. This chemokine has been proposed to be a key link between inflammation and angiogenesis. The aim of this study was to determine whether preeclampsia and delivery of a small for gestational age (SGA) neonate are associated with changes in maternal serum concentration of CXCL10/IP-10.

Study design. This cross-sectional study included patients in the following groups: (1) non-pregnant women (N = 49); (2) women with normal pregnancies (N = 89); (3) patients with preeclampsia (N = 100); and (4) patients who delivered an SGA neonate (N = 78). SGA was defined as birth weight below the 10^th percentile. Maternal serum concentrations of CXCL10/IP-10 were measured by sensitive immunoassay. Non-parametric statistics were used for analysis.

Results. (1) Patients with normal pregnancies had a significantly higher median serum concentration of CXCL10/IP-10 than non-pregnant women (median 116.1 pg/mL, range 40.7–1314.3 vs. median 90.3 pg/mL, range 49.2–214.7, respectively; p = 0.002); (2) no significant correlation was found between maternal serum concentration of CXCL10/IP-10 and gestational age (between 19 and 38 weeks); (3) there were no differences in median serum CXCL10/IP-10 concentrations between patients who delivered an SGA neonate and those with normal pregnancies (median 122.4 pg/mL, range 37.3–693.5 vs. median 116.1 pg/mL, range 40.7–1314.3, respectively; p > 0.05); (4) patients with preeclampsia had a higher median serum concentration of CXCL10/IP-10 than normal pregnant women (median 156.4 pg/mL, range 47.4–645.9 vs. median 116.1 pg/mL, range 40.7–1314.3, respectively; p < 0.05); (5) patients with preeclampsia had a higher median concentration of CXCL10/IP-10 than those who delivered an SGA neonate (median 156.4 pg/mL, range 47.4–645.9 vs. median 122.4 pg/mL, range 37.3–693.5, respectively; p < 0.05).

Conclusions. Patients with preeclampsia have significantly higher serum concentrations of CXCL10/IP-10 than both normal pregnant women and mothers who have SGA neonates. These results are likely to reflect an anti-angiogenic state as well as an enhanced systemic inflammatory response in patients with preeclampsia. Alternatively, since preeclampsia and SGA share several mechanisms of disease, it is possible that a higher concentration of this chemokine may contribute to the clinical presentation of preeclampsia in patients with a similar intrauterine insult.     

The pattern and magnitude of “in vivo thrombin generation” differ in women with preeclampsia and in those with SGA fetuses without preeclampsia

Objective: We aimed to determine the differences in the pattern and magnitude of thrombin generation between patients with preeclampsia (PE) and those with a small-for-gestational-age (SGA) fetus.

Methods: This cross-sectional study included women in the following groups: (1) normal pregnancy (NP) (n?=?49); (2) PE (n?=?56); and (3) SGA (n?=?28). Maternal plasma thrombin generation (TGA) was measured, calculating: (a) lag time (LT); (b) velocity index (VI); (c) peak thrombin concentration (PTC); (d) time-to-peak thrombin concentration (TPTC); and (e) endogenous thrombin potential (ETP).

Results: (1) The median TPTC, VI, and ETP differed among the groups (p?=?.001, p?=?.006, p?p?p?=?.02) groups; 3) patients with SGA had a shorter median TPTC and a higher median VI than the NP (p?=?.002, p?=?.012) and PE (p?p?=?.006) groups.

Conclusions: (1) Patients with PE had higher in vivo thrombin generation than women with NP and those with an SGA fetus; (2) the difference in TGA patterns between PE and SGA suggests that the latter group had faster TGA, while patients with PE had a longer reaction, generating more thrombin. This observation is important for the identification of a subset of patients who might benefit from low molecular-weight heparin.     

Maternal plasma-soluble ST2 concentrations are elevated prior to the development of early and late onset preeclampsia – a longitudinal study

Objective: The objectives of this study were to determine (1) the longitudinal profile of plasma soluble ST2 (sST2) concentrations in patients with preeclampsia and those with uncomplicated pregnancies; (2) whether the changes in sST2 occur prior to the diagnosis of preeclampsia; and (3) the longitudinal sST2 profile of women with early or late preeclampsia.

Materials and methods: This longitudinal nested case–control study included singleton pregnancies in the following groups: (1) uncomplicated pregnancies (n?=?160); and (2) those complicated by early (<34 weeks, n?=?9) and late (≥34 weeks, n?=?31) preeclampsia. sST2 concentrations were determined by enzyme-linked immunosorbent assays. Mixed-effects models were used for the longitudinal analysis.

Results: (1) Plasma sST2 concentration profiles across gestation differed significantly among cases and controls (p?22 weeks of gestation; cases with late preeclampsia had higher mean concentrations at >33 weeks of gestation (both p?Conclusions: Maternal plasma sST2 concentrations are elevated 6 weeks prior to the clinical diagnosis of preeclampsia. An increase in the maternal plasma concentration of sST2 may contribute to an exaggerated intravascular inflammatory response and/or the Th1/Th2 imbalance in some cases.     

Soluble TRAIL in normal pregnancy and acute pyelonephritis: a potential explanation for the susceptibility of pregnant women to microbial products and infection

Abstract

Objective: Pregnancy is characterized by activation of the innate immune response demonstrated by phenotypic and metabolic changes in granulocytes and monocytes. This state of activation has been implicated in the pathophysiology of multiorgan dysfunction of pregnant women with acute viral or bacterial infection. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is one of the mediators responsible for neutrophil apoptosis. Gene deletion of TRAIL results in delayed neutrophil apoptosis and resolution of inflammation after the administration of bacterial endotoxin. The aim of this study was to determine whether maternal plasma concentrations of the soluble form of TRAIL (sTRAIL) differ in women with uncomplicated pregnancy and those with acute pyelonephritis.

Method: A cross-sectional study was conducted to include women in the following groups: (1) non-pregnant (n?=?23); (2) uncomplicated pregnancies (n?=?93) and (3) pregnancies with acute pyelonephritis (n?=?23). Plasma concentrations of sTRAIL were determined by enzyme-linked immunoassay.

Results: (1) Women with uncomplicated pregnancies had a lower mean plasma sTRAIL concentration (pg/mL) than non-pregnant women (31.5?±?10.1 versus 53.3?±?12.5; p?<?0.001); (2) plasma sTRAIL concentrations did not change as a function of gestational age (Pearson correlation?=??0.1; p?=?0.4); (3) the mean plasma sTRAIL concentration (pg/mL) was significantly lower in pregnant women with acute pyelonephritis than in those with uncomplicated pregnancies (20.5?±?6.6 versus 31.5?±?10.1; p?<?0.001) and (4) among patients with acute pyelonephritis, patients with bacteremia had a significantly lower mean plasma concentration of sTRAIL (pg/mL) than those without bacteremia (15.1?±?4.8 versus 24.7?±?4.6; p?<?0.001).

Conclusion: Women with uncomplicated pregnancies are associated with a significantly lower mean maternal plasma concentration of sTRAIL than that observed in non-pregnant women. Moreover, a further decrease in plasma sTRAIL concentration was observed in pregnant women with acute pyelonephritis, and this could account, at least in part, for the exaggerated intravascular inflammatory response previously reported in pyelonephritis during pregnancy.